Not Applicable
Not Applicable
1. Field of the invention
This invention relates to mufflers and particularly to mufflers having two baffles in one housing.
2. Description of the Prior Art
In modern small aircraft design, the muffler system consists of a single housing that is fitted with a pair of baffles. The two exhaust manifolds of an engine feed into this single muffler. FIG. 1 is an interior view of a typical prior art muffler. Here, the muffler housing 1 has two baffle elements 2 that connect to inlets 3. Exhaust gasses 4 enter the muffler from both sides of the housing as shown by the arrows. Once these gasses pass through the baffle elements 2, they outflow through the exhaust 5. Ideally, these gasses would pass from the baffles directly through the exhaust 5. However, in practice, these gasses circulate within the can as shown by the curved lines. This mixing of the exhaust gasses cause problems with engine performance. It causes increased back pressure, can reduce horse power and, under certain circumstances, can cause exhaust coming from one manifold to flow through the other manifold, back into another cylinder during valve overlap and when the exhaust valve is off its seat.
The instant invention overcomes these problems. An exhaust has two isolated muffler elements (i.e., a baffle element covered by a xe2x80x9ccanxe2x80x9d) in one container (shroud). This allows the exhaust from one manifold to be muffled and exhausted independently of the other manifold""s exhaust. Moreover, the muffler is the same size as existing mufflers, so that it fits into the space of the prior art mufflers. Using two independent muffler elements eliminates all of the problems discussed above and increases the engine horsepower without reducing efficiency. It is a true dual-exhaust system.
The outer shroud is also designed to act as a heat exchanger. Fresh air can be pulled through the shroud to be heated for cabin heat and for carburetor heat. The shroud, which surrounds the muffler elements, has space around the cans, through which the fresh air passes. Inlet and outlet ports are provided to allow hoses to be connected as needed.